The present invention relates to a cold storage incorporating a cooling unit including a compressor and a cooler under a thermal insulating housing constituting therein a storage room.
In a cold storage of this kind hitherto used as a low temperature showcase, a machine room is constructed under a storage room formed in a thermal insulating housing, and the bottom wall of the thermal insulating housing is formed with a cold air discharge port and a cold air suction port communicating with the machine room. A cooling box having openings in its upper surface is provided in the machine room so as to abut against the bottom wall of the thermal insulating housing, and a cooler and its blower constituting a cooling unit are arranged in the cooling box. Then, the interior of the storage room and the cooling box are communicated with each other through the cold air suction port and the cold air discharge port. Moreover, under the cooling box of the machine room, a compressor, a condenser, its blower and the like forming the cooling unit together with the cooler are arranged on a mounting base provided with casters on its bottom surface for moving, thereby constituting a publicly known cooling medium circuit.
The cooling box is also provided on the mounting base detachably from the bottom wall of the thermal insulating housing. The cooling box and the cooler, its blower, the compressor, the condenser and the like are freely admitted into or removed from the machine room together with the mounting base with the aid of the casters so that the cooling unit can be separated from the thermal insulating housing (refer to Japanese Patent Application Laid-Open No. 105,058/2000).
In the prior art construction as described above, however, as cold air leakage would occur through clearances created between the openings of the upper surface of the cooling box and the cold air discharge and suction ports, after the mounting base has been admitted in the machine room, the cooling box having the cooler and its blower arranged therein must be lifted and fixed to the bottom wall of the thermal insulating housing by fixtures or the like. Therefore, the mounting operation would become complicated as a problem to be solved. At this time, moreover, the cooling box must be fixed in a position corresponding to the cold air discharge and suction ports formed in the bottom wall of the thermal insulating housing so that the positioning would become difficult, resulting in further deterioration of operationality. It may be envisioned that the cooling box is lifted together with the mounting base on which the cooling box is fixed and is then fixed to the bottom wall of the thermal insulating housing. However, as the compressor, the condenser and the like in addition to the cooling box are arranged on the mounting base, the total weight may be frequently more than 40 kg, it would be very troublesome to carry out the lifting operation every time maintenance operation is effected. Therefore, there has been a requirement for simple procedure for the mounting operation.